The suspicious death of Rwanda’s former spy chief in a plush Johannesburg hotel is resurrecting allegations that Western-backed President Paul Kagame is orchestrating a campaign to kill opponents at home and abroad.

South African police opened a murder investigation after former Col. Patrick Karegeya’s body was discovered on New Year’s Day.

“He was found in the hotel room dead on the bed,” said police spokeswoman Lt. Col. Katlego Mogale. “A towel with blood and a rope were found in the hotel room safe. There is a possibility that he might have been strangled.”

Rwandan opposition leader Theogene Rudasingwa identified the hotel as the Michelangelo Towers and called the death an assassination that fit a pattern of attacks against prominent opponents of Kagame.

“By killing its opponents, the criminal regime in Kigali (Rwanda’s capital) seeks to intimidate and silence the Rwandan people into submission,” he said in a statement. “The regime is hugely mistaken. Such criminal activities make Rwandan people more emboldened to struggle to remove the dictatorship.”

Karegeya, 53, was a wartime ally from Kagame’s days as a rebel leader but later parted ways with the Rwandan president and reportedly fled to South Africa in 2007. Karegeya told a journalist a month ago that his work organizing the opposition to Kagame was risky and could cost him his life. He also said his daughter’s Rwandan passport was revoked on Kagame’s orders while she was trying to leave Uganda, where she grew up in exile, and that Kagame blocked his own quest for work with the United Nations.

The Rwandan government vehemently denies targeting dissidents, and Rwandan High Commissioner Vincent Karega told local broadcaster eNCA on Thursday that talk of assassination is an “emotional reaction and opportunistic way of playing politics.” He urged people to wait for the police report in South Africa, which has one of the world’s highest murder rates.

Kagame’s spokesman and Rwanda’s foreign minister could not be reached by telephone and did not respond to emailed requests for comment.

Kagame and his associates have governed Rwanda since his rebel forces took control 20 years ago, winning praise from Western leaders who point to how he has turned around an impoverished and war-ravaged nation into an efficient technology hub. Rwanda has reliable electricity and road systems and some of the highest rates of literacy and good health in Africa. Former U.S. President Bill Clinton visited the country with his daughter, Chelsea, in August, and former British Prime Minister Tony Blair is a frequent guest.

Critics, however, say those successes have come at the cost of a ruthless dictatorship. Kagame has won elections but without opposition, because its leaders were either jailed or in exile.

Kagame has long been accused of extra-territorial killings, including ones committed when Karegeya was the feared boss of Rwanda’s external security agency.

In 1996, former Interior Minister Seth Sendashonga and businessman Augustin Bugirimfura were gunned down in the Kenyan capital, Nairobi. Kenya detained a Rwandan diplomat briefly and then released him — under pressure from Kagame, dissidents contend. Also in Nairobi, legislator and former government intelligence chief Theoneste Lizinde was killed in 1998. Two years later, presidential adviser Assiel Kabera was shot and killed in Rwanda, reportedly by men in military uniform.

Kagame’s Rwandan Patriotic Front, made up of members of the Tutsi tribe, came to power in 1994 when it ended the genocide in which some 800,000 Tutsis and moderate Hutus were killed.